AOpen B2945 Manual Manual page 24

Automatic Mode
Once you enable this mode, Power Master will detect your processor true
loading automatically. When the processor loading is heavy, Power Master
will raise your processor's clock frequency to meet your requirement. On
the contrary, when the processor is in low loading, Power Master will drop
the clock frequency to reduce the noise from processor fan.
Performance Mode
Once you enable this mode, Power Master will detect your processor true
loading automatically. In this mode, the processor's performance will
always be the highest. When the processor loading is heavy, it will raise
your processor's clock frequency higher. On the contrary, the processor will
be getting lower.